Overcoming hurdles – efficiency and performance on two legs

在技术上的两足机器人中，可以通过调整系统的机械部件(如柔性机构形式的弹簧和阻尼器)来调整系统的自然动态，以实现高能效。效率的提高允许使用更小的致动器，这进一步减少了传动系统中的损失。然而，由于这种缩小规模，这种高度专业化的系统不能执行像跳跃这样的运动，这种运动在短时间内需要非常高的功率。然而，跳高和跳远是两足步行系统的基本动作，应该可以克服障碍。然而，这些跳跃动作只是零星发生的。因此，它们所需的功率可以通过释放机械储能(预加载弹簧)一次提供。由于柔顺机构已经集成到机器人系统中，以优化自然动力学，其目的是在执行跳跃时将它们用作能量存储。使用顺应机制来优化行走的自然动力学和效率，并作为高性能跳跃的能量储存的步行系统，在文献中并不为人所知。因此，该项目的目标是为促进步行效率和跳跃性能的柔顺机构的集成和设计提供科学依据。为此，顺应机构将具体利用非线性特性，在运行期间被动或半主动地在不同运行模式之间切换。以基于模型的方式研究了两足步行器的运动。柔顺机构由运动学和动力学模型描述。包括柔顺机构的两足步行器的运动模型一方面被用作整个系统开发和优化的仿真基础；另一方面，它是升级和控制现有原型的基础，所开发的机构在其上进行验证。在能源效率高的步行和克服障碍被认为是先决条件的情况下，例如在外星步行系统或长途救援任务中，可以应用这些结果。此外，这些方法可以用来实现新的特性，并在它们之间经济地切换(最好是不使用能源)。将获得的研究结果可用于需要新的复杂特性曲线和从一条特性曲线切换到另一条特性曲线的能力的其他技术系统，特别是以无能量的方式。

In technical bipedal robots, the system's natural dynamics can be adjusted to achieve high energy efficiency by tuning mechanical components of the system, such as springs and dampers in the form of compliant mechanisms. The increased efficiency allows for the use of smaller actuators, which further reduces losses in the drivetrains. However, due to this downsizing, such highly specialized systems cannot perform movements like jumps, which require very high power for a short time. High jumps and long jumps, however, are fundamental movements for bipedal walking systems that are supposed to overcome obstacles. However, these jumping movements occur only sporadically. Hence, the required power for them can be provided once by discharging a mechanical energy store (preloaded springs). Since compliant mechanisms are already integrated into the robot system in order to optimize the natural dynamics, the aim is to use them as an energy store when performing jumps. Walking systems that use compliant mechanisms both to optimize the natural dynamics and efficiency of walking and as energy storage for high-performance jumps are not known from the literature. Therefore, the goal of the proposed project is to provide the scientific basis that will advance the integration and design of compliant mechanisms for both walking efficiency and jump performance. To this end, the compliant mechanisms will specifically use nonlinear characteristics to passively or semi-actively switch between different operating modes during operation. The movements of a bipedal walker are investigated in a model-based manner. The compliant mechanisms are described by kinematic and dynamic models. A motion model of the bipedal walker that includes compliant mechanisms is used on the one hand as a basis for simulations for the development and optimization of the overall system; on the other hand, it is the basis for upgrading and controlling an existing prototype on which the developed mechanisms are validated. The application of the results is possible where energy-efficient walking and overcoming obstacles is considered a prerequisite, for example in extra-terrestrial walking systems or in long rescue missions. In addition, the methods can be used to realize new characteristics and to switch between them economically (preferably without energy). The results of the investigation to be obtained can be used for other technical systems where new complex characteristic curves and the ability to switch from one characteristic curve to another, especially in an energy-free way, are required.